Metallizing process and apparatus.



I. M. LONGYEAR &1.T.JONF.S.

MEALLIZING PROCESS AND APPARATUS. APPLlcmbN msu H123. m15. RENEWED Nov. 2, 191s.

1,28%834. l Patented Dec. 81, 1318.

4 SHEETSHEEU:I

1. wi. LGNGYEAR 1. mom-s.

MEHLLZING PROCESS AND APPARATUS. AFNIC TIN FILED FEB. 23. 1.915. RENEWED NOV. 2. 1918.

lssh Patented Dec. 31, 191s.

Y S [ETS-SHEET 2. K E2; .3' 4 H I v1. M. LUNGYEAR 1A joNEs.

METALUZIIEG PROCESS AND APPARATUS.

` APFUCA-TiON FILED FEB.23.1915. RENEWED NO V. 2. |928. li Mmmm M131, 1918,

SHEET 3* l 4 SHEETS- 2. ma. A Patente Dec. 3L lQl, 4 @MEETS-Snam 4.,

l. M. LONGYERYGL l. T. GNES.'

METALLIZING ROCESS AND PPAEATS.

APPLICATIN FILED FEB. 23. NIS. RENWEB NOV. 1,289,834.

"UNITED srarss rarnn'r orrron.'

JGHN M. LONGYEAR AND JOHN T. JONES, OF MARQUETTE. MICHIGAN, ASSIGNORS TO NEW METJLS-PROCESS CMPANY, 0F CHICAGO, ILLINOIS, A CRPORATION OF ILLI- METALLIZING PROCESS AND APPARATUS.

Maasai.

Specification of Letters Patent.

Patented Deo. Si, i.

.application led ebruary 23, 1915, Serial No. 9.889. Renewed November 2, 1918. Serial No. 260.914.

To ali whom may concern:

lie it known that we, Jorn M. LoNoYnAn The process herein described constitutesv an improvement on th" inetallizing process set forth in the application oit Albert (i. Jones, No. '827.358, tiled March 2G, 1914.

The primary object of the invention is to provide an improved lnetallizing pro-'ess which will reduce the cost ot the metallizing operation. and to provide an improved furnace of durable character. by means ot which the improved process may be advantageously p actised The improved apparatus will be described. and the improved process `will be explained in connection therewith.- The @referred construction of the apparatus is illustrated inthe accompanying drawings, in which v Figure l represents a broken, vertical. seetional View of xnetallizing apparatus adapted to the practice of the process herein de scribed: Fig. 2. a horizontal section taken as indicated at line 2 ot Fig. 1: Fig. 3, a 'broken elevational' view talfen as indicated at line 3 of Fig. l; Fig. i. a broken. vertical section taken as indicated at line l ot Fig. l; and Fig. o. an enlarged broken, vertical sectional view showingr a detail of a twyer and of means for charging a relatively small amount ot 'fresh solid Jfuel directly into the (le-oxidizing chamber which constitutes one section ot the metallizing t'urnace or apparatus illustrated.

ln the preferred construction otl the apparatus which is illustrated. .\.i'ep1esia1ts an upright furnace comprisinga base-section or soaking-pit A', a super-posed deoxidizing chamber A2. pre-heating chambers A, A and .i5 in successively superposed relation above the desoxidizing chamber. and a chimney or stack AG superposed above the uppermosty pre-heating chamber A5: B. B. 1neanstor charging a mixture of ore and distilled solid t'uel (coke or char-y coal) into the uppermost pre-heating chamber: C. C. means for charging fresh solid fuel containing hydrogen and carbo-hy d ates (coal or wood) directly into the deoxidizing-chamber A2: D. a series of airtwyers for supplying air to the (le-oxidizing chamber and the pre-heatingchambers at the several levels indicated: and E. E, a pair of stand-pipes connected with the several twyers, and which may contain air under small pr ssure` supplied from a blower or blowers E.

r1 `he furnace A may be ot any suitable construction. and of any desired form. In the illustration given` the furnace is of rectangula1.for1n. and may conveniently have an internal width otl four to eight feet. The deoxidizing chamber A2, particularly, should have its` walls adapted to withstand high teniperatures.

lt is pr ferred to contract the internal dimensions of the. furnace at the junctions of the sections enumerated` in order that the burden or stack ot` materials contained in the turnacemay be supported. or partially supported. in sections. that. is, at'different.

levels. In the illustration given. the lateral walls of the furnace are provided with internal shoulders havingsloping upper walls l. and undercut lower walls 2. rlhe sloping walls l at each level are preferably ot' such an angle and ot such inward extension as to almost, but not quite. support the burdensection in the chamber t'or which the sloping walls form a rudimentary bottom or support. The twyers D extend through the walls` are adjustable. and are preferably i disposed in a plane below the sloping walls 1. rThe twyers (except the lowcrmost ones) preferably project within the furnace somewhat beyond the shoulders afforded by the. slopimcr walls 1. and thus serve as a supple mental supporting means whereby (with the slmulders` l) the burden is virtually sup `ported in sections. A further object which is gained by this arrangement is to introduce the air far enough wit-hin the burden so that it will be ditiused throughout the burden in each chamber or section of the. furnace, thus avoiding the possibility of a dead core. The twyers may he of rectangular t'orm and arranged in horizontal series at the sides of the furnace, at the various levels. Each twyer may be of the construction shown in d tail in Fig. 5. That is, the twyer may be of box-form and water-cooled, as by means of pipes 3. The twyers, as indicated, are adjustable through the walls of the furnace, and have slip-joint. connection With air-pipes 4 which are supplied from feeders 5 arranged at different levels at the sides of the furnare and communicating with the stand-pip s E through pipes 6. rThe admission of air through the pipes` el. may be controlled bv means of valves 4a.

The means for supplying a mixture of ore and distilled solid fuel (colte or charcoal) to the upper portion of the furnace may be of any desired construction. The means B illustrated comprises a hopper having an inclined spout 8 leading through the furnace-wall and equipped With a lidor cove-r 9. This may be regarded as a lconventional illustration, however, of any suitable means for introducing the charge into the upper portion of the furnace.

Any suitable means may be employed for introducing fresh solid fuel, such as coal or wood7 directly into the cle-oxidizing chamber. The means C comprises a hopper 10 which supplies a chute 11 in which Works a plunger actuated by a piston contained in a cylinder 1'2. rl`he hopper 10 is fitted with a lid 13? The fuel-introducing device C may be regarded as a conventional illustration of any suitable means for introducingfresh fuel into the de-oxidizing chamber A?.

At the bottom of the chamber A. is provided discharge means F, which may be any approved device for removing the metallized ores in solid form, the gangue, and thc unconsumed distilled solid fuel. vtn the form illustrated, the means F comprises discharge-passages 14 guarded by doors 15. through which the materials may be Withdrawn or discharged into a water-bath 16.

For convenience in attending the furnace. the walls of the furnace are shown provided at the several levels with platforms 17.

While the dimensions of the chambers of the furnacel may vary, within reasonable limits, it is desirable that the several chambers s hall be of comparatively low height,

- the purpose being to avoid undue packing of the burden and any-detrimental crush; ing of the coke or charcoal used. To this end, it is preferred to limit the height of the cle-oxidizing chamber and each of the other superposed chambers to about 12 or 15 feet. The chimney A may be of any desired height. lt is preferred to have the chimney of such height that little or no artificial erably fed in a crushed condition. say of a,

size of one inch or less .indimensions, with a charge of colte (or charcoal) through t.the

Leccese hoppers B into the upper end of the fun nace, that is, into the uppermost pre-heating chamber.

It is desirable to feed through the furnace distilled solid carbonaceous fuel (coke or charcoal) having many times the bulk or volume ofthe ore, and preferably having about twice the Weight, or more than twice the Weight, of the ore. This is particularly true in dealing with high-grade ores. lt is also desirable to feed directly into the deoxidizing chamber A2, as through the charging-devices C, a relatively small amount of fresh solid fuel from which hydrogen and carbohydrates may be distilled, such as bituminous coal or Wood. Such fuel not only supplies gases of high value in eecting the cle-oxidation of the metal oxids` but constantly replenishes the coke or charcoal, as the case may be.

As an illustration, in dealing with a highgrade iron ore, the materials may be used in the proportion of 400 pounds of coke, 100 pounds of bituminous coal, and 250 pounds of ore, the fuel having approximately twice the Weight of the ore and being approximately five times as large in volume as the ore. lf Wood and charcoal be used in place of coke and coal, the disparity in volume is much greater. pounds of ore one may use 9G cubic feet of charcoal and cubic feet of wood. The proportions may be' varied to gain the best and most economical results. In any case, it is preferred to use the fuel mainly in comparatively large lump or block form, although this is not indispensable. Cord or slab u'ood 1G inches long maybe conveniently used, and Where coal is used. it is preferably used mainly in large lumps. As ivill he eX- plained, the colte (or charcoal) is used over and over again. being gradually reduced in si-Ze, but being constantly replenished .by freshly formed coke or charcoal) `when the process is carried on in the preferred metals in solid form, Ythe uneonsumed portions of the solid fuel. and the gangue are removed from the bottom of the furnace. In beginning the opeiatioinsolid fuel may be introduced into the furnace and a .tire lighted, and the materials in proper proportions may ,be introduced as the worlprogresses. W'hen the process is under ivayl sufficient air isidmitted through the lower` most twyers 'to provide in theloiver per l tion of the de-oX1d1zing"chamber A? high For illustration. with 2240.

depends upon the character of the ore. In

lean ores, containing -some natural linx, it'" is desirable to avoid too lhigh a temperature. It is preferred to so balance the operation that the temperature Willdecrease gradually from the bottom 'of the de-oxidizing chamber A2 to the upper pre-heating chamber, somewhat as indicated by the temperaturescale shown onFig. l of the drawings. Accordingly, at the upperlevels, air is admitted in limited, and, if necessary, successively reduced quantities, with a view to burning the deoXidizing gas which passes upwardly through the burden from the deoxidizing chamber and pre-heating the ore in the pre-heating chambers. lt is to be observed, however, that several zones of i ntensified heatoccur at the inner ends of the twyers at the successive levels, each of said zones of intensified heat, however, being of` successively reduced intensity as the upper portion of the furnace is approached. In the cle-oxidizing chamber A2 a very intense zone of heat occurs in the vicinity of the lowermost twyers, carbon-dioxid being produced. T his changes to carbon-monoxid at a. somewhat higher level in the chamber A2, the temperature in the chamber A2 being nevertheless of such a high degree of heat as to enable a rapid interchange of oxygen to occur. The carbon-dioxid, coming in contact with the highly heated fuel, changes to carbon-monoxid; and the carbon-monoxid, comingA in contact with the highly heated ore. robs the ore of its oxygen, the interchange of oxygen continuing rapidly. lt may happen, also, that in thelowermost prehcating chamber A3, and even in the chamber A4, some of the solid fuel may still jbe of high enough temperature to be attacked by the oxygen entering at the twyers for said chambers, but as the upper portion of the furnace is approached. the attack upon the distilled -fuel becomes less and less, owing to the reduction in temperature; and, finally, under ideal conditions, the le-oxidizing gas is aloneburned in the upper portion of the furnace, and after complete combustion, the products pass upwardly through the smokestaclt. As has been indicated, the fresh fuel introduced directly into the dii-oxidizing chamber A2 provides hydrogen-gas and mirbo-hvdrates which-are of great value in reducing the metal oXids. thesegascs operating under conditions which enable the most rapid interchange of oxygen to occur,l as the process of robbing the metal'oxids of their oxygen proceeds. The fresh fuel introduced serves incidentally to replenish the supply of distilled solid fuel.

llroui the' foregoing. it will be undo-rstood that as the ore and the distilled solid fuel in which the ore-portions are practically isolated from each other settle down wardlv through the vpre-heating chambers, the burden in the pre-heating chambers is pre-heated under conditions which will en able much ,of the ore to be ile-oxidized. especially in the lowermost pre-heating chamber A3, as the burdelr slowlyv settles therethrough. `When the materials reach the (le-oxidizing chamber A2, they are at such high temperature as to enable a rapid interchange of oxygen 4to occur, and here the metallizing operation is mainly completed and the metals may be, by the high degree of heat in the lower portion of the deoxidizing chamber, so fused .or softened as to cause the metal particles to run together or agglomerate in globes, or masses of globular lumps; but, owing tothe isolation of the ore-clusters or groups from each .other and their practical envelopment by pieces, lumps or blocks of` solid carbonaceous fuel, while this action takes place, no molten bath is formed, and general fusing of the materials is avoided. It may happen that isolated pools of molten metal and isolated pools of molten gangue may form, which will congeal as the materials settle down into the soaking-pit A. The formation of a general bath is avoided, however, and the contamination of the metals is. largely avoided. ln dealing with manganese ore, particularly, isolated pools of pactieally pure metal may form, which will congeal in the form of large smooth lumps.

In the passage of the ore and fuel through the cle-oxidizing chamber, myriads of minute metallized particles or globules may adhere to the coke or charcoal, and when the coke or charcoal is again fed through the furnace, these minute particles become fused sufficiently to coalesce, forming globes or globular masses, or masses of globes or globv ules, thus putting the metal in such tangible form` or size as to enable it to be separated or concentrated by any suitable method. The sizes of the metal pieces may vary greatly, but eventually, whether of veryv fine mesh, or of meshes of very considerable size, say of sizes ranging up to one inch or larger, the metals arev nevertheless produced in lumps of such tangible size. as to enable them tobe readily collected, and with the metal in setfor fixed condition, so that re-oxidizing will not occur. As has been in dicated, it may happen, especially with rich iron or manganese orcs. that isolated pools of metals will form and will congeal as the materials descend below the hottest zone', and it may happen, where the gangue contains a naturaltlux, that small isolated fused portions or pools of gangue will form and solidify as the charge slowly descends. In any case, the carbonaceous orc-spacing Ina-- created will pass freely through the burden, ,l

terials should be in such abundance and the air-suppl y should be so regulated as to avoid destroying the spacing function of the fuel. That is, a large preponderance of distilled solid fuel should be carried wholly through the cle-oxidizing chamber, and bathing, or generalfusing of the charge is to be avoided. As the materials settle down in the soaking-pit Af,tl1e temperature decreases; and inasmuch pas' de-oxidizing conditions are maintained in the chamber A, the de-oXi dizing action will continue, especially in the hotter upper portion of the chamber A', so long as there remain any metal oxids into Contact with which the ,de-oxidizing gas can come.

It is noteworthy that because of the great preponderance of solid fuel which has a spacing function, the draft through the burden may be securedwith little or no artificial pressure; and because of the fact that the burden is largely supported in sections, the creation of any large crushing pressure upon the burden in the furnace is avoided, so that the air from the twyers and the gases Any excessive pressure would result in crushing the coke or charcoal and in so compacting the-burden as to seriously interfere with the practice of tbe bathless metallizing process herein describedt On the other hand, in the utilization of the process herein described, it is possible to use coal of inferior coke-producing quality, or wood of inferior charcoal producing quality. For instance, it is possible to use coke that would not withstand the pressure of ordinary blast furnace operations.

By the practice of the improved process, it is possible to produce iron of high purity, possessing about twice the value of pigr iron on the market. Moreover, it is entirely fea sible to obtain metals by the direct process Without the use of fluxes and operating with little or no artificial draft or pressure. Because 'of the avoidance of the production of a general bath, it is possible to prevent the great contamination of the metals which occurs when all the materials are fused, as in blast n'acticeand'large economies result from tue useful application of a very high percentage ofihe heat units developed in lthe operation.

lu treating iron ore, it is feasible, by the improved process, to produce comparatively large masses of coalesced or agglomerat'ed globes or globules of iron, but Without producing a bath and without general fusing of the gangue, the metal being in a highly pure state and capable of being removed from the furnace in solid form.

Manganese may be produced in comparatively large globular masses, as Well as in smaller butvstill thoroughly tangible globules by the same treatment as has been described Lacasse .for iron ore. Copper may be produced in VTV"the same manner, and several metals, such as copper and iron, may be produced by one and the same treatment. ln dealing simply with a copper ore, somewhat less fuel need be used, and copper may be produced at a somewhat lower temperature than is the case with iron.

@Wing to the fact that zinc and lead volatilize at a temperature of approximately 22000 F., they must either be treated sepa-- ,move the large metal glo ules, after which.

the ore may be n'ely ground and snbiected toa tabling or concentrating; operation; or any other the metal from the ore may be employer. It has been found, for illustration, that a copper ore, after subjection to a metalliziug referred method of recovering l process of this character, is amenable-to treatment in accordance with the lirzfettv vprocess described in U. S., Reissue Fatent No. @,517 and that concentration with high degree of saving can be effected, even lil@ Where the metals arev of exceedingly fine mesh.

ln any given case, any suitable method for separating the distilled fuel from the gta-Ligue and metals, and for. separating the metals from the' gangue, may be employed, and the distilled fuel may be fed again through the furnace, mixed with the proper proportion of fresh ore.

lt may be added that, if desired, highly?? refractory blocks or. lumps, such` as silica boulders. mav be used for s acin. urposes and passed with the coke or charcoal through the furnace. In such case, both the colte, or other lump fuel, and the boulders, would serve as spacers adapted to practically iso latc the oregroups. ln any case, however, it

would be necessary to supply sutlicient fuel to produce the necessary (le-oxidizing gas and such high temperature as would ,be sufficient to enable a rapid interchange of oxygen to occur and in some cases to effect fusing or partial fusing, and thus to enable the globing or coalescing effect of the metals to take place, care bein;Y taken to Fpreserve the spacing function of the refractory, pieces throughout and avoid the formation of a bath.

From the foregoing, it will be understood that preferably a limited supply of air 1s assess-a tially isolated therein, and burned 4bythe use.

of limited, and if necessary, successively-rsduced air-supplies introduced into the burden at 'different levels, the solid fuel being attacked less and less as the upper part of the stack is approached; and that finally the air-supply introduced to the upper portion of the furnace is so limited and burned at such low temperature as tomerely unite with the `previously-formed combustible gases, without. substantially attacking.: the solid fuel, so that the freshly introduced ore andI solid vfuel are merely pre-heated and the products oi substantially complete combustion pass up the chimney. Thus. the preheat ing is accomplished by burning the combustible gases produced below within the treshly introduced portion of the burden, thereby securing intimate contact between the burning gases and all' portions ot the burden, so that the most. economical results are obtained.

It should be noted, perhaps` that owing to the thorough predicating ofthe burden. less air will he required in the (le-oxidizing chamber A2 than might be supposed. ln any case, the air is to be regulated to secure the best results.'

In practice. the method .of feeding materials to the furnace maybe varied, accordin LT to conditions. It green or wet wood loe used for fuel, it may be ted in at a higher level, so that the water will be driven ott before the wood reaches a lower and hotter zone. ln such case, the wood will he thoroughlv dried and `someivhat charred during the pre-heating. the volatile hydro-carbone being mainly liberated at a lower level where they can be utilized most eliiectively. In some eases, it may bo desirable to toed all or a large portion of the tuelI in at lower level than that* at which the ore is'fed. Much will depend upon the character ot the ore and the solid fuel used. ln' any event, it will he necessary to maintain sutlicient interstitial passages tor the. air and ,gases through the burden and it will he necessaryr to maintain a large preponderance of solid fuel in the lower, hotter rone` .l

The foregoing.r detailed description has l upper portion of Vsaid stack.

`been given for elearness of understanding fpnly, and no unnecessary limitation should -*he understood therefrom, but the appended "claims should be construed as broadly as permissible in view of the prior art. lt is our intention to claim all of our invention as it shall appear in view ot' the prior art, regiardless ot any variations which may loe practised. What we claim as new and desire to secure 'by Letters Patent is-n l. The bathless process of recovering metals, which consists in burning air in limited regulated quantities at a plurality of levels in a stack of superposed burden-.sections comprising solid fuel and ore-portions substantially isolated therein, without producing a bath, regulating the combustion in such manner as to produce generally a deoxidizing medium throughout the lower rortion of said stack and to provide a nighteniperature metal-fixing. zone near the bottom ot said stack, and to pre-heat, Without substantially attacking. the solidtuel in the 2. The loathless process of recovering metals, which consists in passing.lr through a ysectionally-supported hurdlen comprising solid fuel undergoing combustion and ore- `portions substantially isolated therein, said burden arranged in a stack of superposed sections. air introduced at a plurality ot levels and regulated to produce a high de-oxidizingI and metal-fixing sone near the lower end ot the stal lr, and to attack the solid fuel l0@ in successively reduced degree as the upper end ot the stack is approached.

3. The bathless process of recovering metals, which consists in passing through a sectionally supported burden of distilled solid t'uel undergoingcombustion, and oreportions substantially isolated therein, air so regulated as to produce in one Zone in said stack a temperature exceedingl 2000 l". and in another zone (le-oxidizing gases, thereby eilecting- Inetailiaation and fixing of the metals without producing a Ibath: then passing the (ie-oxidizing rases through superposed sections of such a -hurden and supplying air to burn the (le-oxidizing gases therein under such conditions as to substantiallyr preserve the solid fuel in the upper portion of the burden.

4. The bathless process of recovering met als, which consists in passing through a 12o burden-section of distilled solid tuel undergoing combustion, and ore-portions substantially isolatedA therein, air so regulated as to produce in one zone inthe stack a terl perature exceeding 200001?. and in another `zone` fle-oxidizingl gases, thereby effecting 4oxidizing gases through superposed sections of such a burden and introducing limited Clt supplies of air at a plurality of levels into said sup'erposed sections of'said burden to burn the ie-oxidizing gases therein at successively reduced temperatures as the' upper end ofthe stack or burden is approached.

Thel bathless process of recovering metals, which consists in burning air in limited, but relatively large, quantity, in a lower section of a stack of superposed burden-sections, comprising solid fuel and oreportions substantially isolated therein, Without produeing'a bath, introducing a relatively small amount of fresh solid fuel into the lower section, so regulating the combus' tion in the lower section as to produce a high-temperature cle-oxidizing medium, and a metal-fixing zone; and introducing and burning air in limited regulated quantities at different levels Within the superposed burden-sections, and so regulating the combustion as to attack the solid fuel less and less as the upper end of the stack is approached.

tl: The bathless process of recovering metals, which consists in giving substantial independent support to a'series of superposed burden-sections composed of solid fuel and ore-portions substantially isolated therein, so as to prevent compacting of the stack of materials and crushing of the fuel, While permitting the stack, as a Whole, to settle slowly as materials are Withdrawn from the bottom of the stack; burning a, limited amount of air in a lower burdensection and producing therein al high-temperature (le-oxidizing medium and a metallixing zone; and introducing and burning at different levels within 'the superposed burden-sections limited air-supplies, so regulated that the solid fuel Will be substantially preserved at the upper portion of the stack and the combustible gases produced belouv will be burned in intimate contact with the solid fuel and ore in that zone.

7. The bathless process of recovering metals, which consists in .conlining a stacli comprising superposed burden-sections composed of solid fuel and ore-portions substantially isolated therein, between Walls which serve to contract the stack of materials at a plurality of levels and th'us provide independent support for the burdensections, introducing and burning a limited air-supply Within a lower burden-section 'to 'produce therein a high-temperature de-oxidizing medium and a metal-fixing zone, and introducing and burning Within the burden- `sections at a plurality of higher levels limited air-supplies, regulated to avoid attacking the solid fuel at the upper portion ofthe stack, while burning in contact With the ore and fuel at that point the combustible gases produced below and passing to such point.

8. An ore-reducing furnace comprising a plurality of superposed chambers having lessees fuel, passing the de-oxidzing gases through superposed burden-sections containing ore,

land introducing and burning air therewith at a higher level in the stack, the operation being carried on Without producing a bath. l0. An ore-reducing furnace comprising a plurality of superposed chambers with contracted internal areas at their junctionpoints adapted to 'afford independent support to a plurality of superposed burdensections contained in the furnace, supplemental burden-supporting means at the junction-points, and means for supplying air in limited quantities to the furnace at a 'plurality of levels.

11. A furnace comprising 'a plurality of superposed chambers with contracted internal areas at their `junction-planes adapted to afford supports for burden-sections contained Within the furnace, adjustable supplemental burden-supporting means at said junction-planes, and means for -supplying air to the burden-sections in limited quantities at a plurality of levels.

12. An ore-reducing furnace comprising a plurality of superposed chambers With`conn tracted internal areas at their junctionplanes adapted to afford support to burdensections contained in the furnace, adjustable twyers extending through the walls of the furnace'at or near the junction-planes and adapted to afford supplemental support to the burden-sections, and means for regulating the introduction of air to said twyers.

13. An ore-reducing furnace comprising a plurality of superposed sections With sloping internal Walls at .the junction-planes adapted to afford supportvfor a series of superposed burden-sections Within the furnace, and means for supplying air at diiferent levels, 'having associated therewith adjustable supplemental supporting means for the burden-sections.

14. An ore-reducing furnace comprising a plurality of superposed sections with sloping internal Walls at the junction-planes adapted to afford support for a series of superposed burden-sections Within the furnace, adjust#- able twyers extending through the furnacewalls and associated With the sloping portions of the Walls, and means for regulating the supply of air to said twyers.

l5. An orc-reducing furnace comprising a lower ile-oxuhzmg chamber and a series of superposed pre-heating cli-.nubers` means at the junctions of the chambers for allerdingsupport to a series of supcrposefl burden sections contained in said. chambers, said means permitting continuous feed past them ofthe materials of theV burden-sections, means for supplyinga limited amount of air fo the deoxidizing chamber, and means .for

supplying air in limited quantities at different levels to the pre-heating chambers.

16. An ore-reducingr furnace comprising e plurality of superposed sections, means at the junctions of said sections for affording support t superposed 4binden-sections contamed in the furnace, means for introducing fresh solid fuel into a lower section,

,means for introducing distilled solidfuel and ore into the upper section, means for supplying air in hunted quantities at a plurality of levels, and means for removing` unl consumed fuel, enligne and metals in solid form from the lower portion ofthe furnace.

17. An ore-reducing ,furnace comprising a soaking-pit provided at' its base with means for removingr unconsurned fuel, ganguc and metal in solid form, a super-posed (lc-oxidizing-chaml'ier, a plurality vof superposed preheating chambers. means for introducing ore and fuel into the upper portion of the f furnace, and means for supplying air in rei,-

ulalole quantities at a plurality of levels.

18. An ore-reducing furnace comprising a soaking-chamber provided at itsbase with means for removingr unconsumed fuel, gangue and metal in solid form, a superposed ile-oxidizingr chamber, twycrs at the junotion of said chambers, a plurality of superposcd pre-heatingchambers, twyers at a` fording independent supports for the-hun deirsections and permitting continuous paz# sage of the materials of the burden-sections. tivyers for supplyingr air in limited quantitics at. a pluralitv of levels to the rle-oxidi2- ing chamber and the pre-heating chamber?, means for supplying orc and fuel to the upper portion of the'furinice, and meansfor supplying air under pressure to the twyers.

20. An ore-reducing furnace for the purpose set forth. comprising a deosidizing chamber of substantially rectangular form and relatively narrow width, a series 0f superposed pre-heating.,y chambers of similar form, means the junctions of said c iamv,bers for affording independent support to a series -of superposed burden-sections contained in the furnace, and means for intron ducing into the burden-sections at a plural ity of levels limited air-supplies.

21. An ore-reducing furnace comprising substantially parallel side walls and end walls, said side walls having internal projeetions dividingr the furnace into u main de oxidizing chamber and a series of superposeti preheating chambers, a plurality of series of twyers extendingr throu h the side Walls of the furnace at a plnrafity of levels and associated with the inward. projections of the side walls, and means for supplying cir in limited quantities to the several series of twyers, Y

22. An ore-reducing furnace comprising: ai pair of side walls spaced a, comparatively short distance apart and provided with in 'tcrnal projections dividing. the furnace into a main cle-oxidizing chamber, and a series Iof superposed pre-heating; chambers, end walls for the furnace, a plurality of series of adjustable twyers extending through the side walls of the furnace at aplurality of levels and associated with said inward projections of the furnace wallsya'nd means for supplying air in regulable quantities to the several series of twy'ers.

JOHN Mi.. LONGYEAR. JOHN T. JONES.

In the presence of- "A ALBERT G. Jonas,

E. W. JONES. 

